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authorgVisor bot <gvisor-bot@google.com>2021-05-14 19:57:47 +0000
committergVisor bot <gvisor-bot@google.com>2021-05-14 19:57:47 +0000
commit69b159307df360bdcda964a468625c25adbd9b5c (patch)
treecf64ba34dd97ec2c823abfa7afe484d09f9388f3 /pkg/buffer/safemem.go
parent042ac2e7170513c5928b36c95b16544f7130cda4 (diff)
parent2ac6b76884c7a8c8b788b4c376098ea48b9fe610 (diff)
Merge release-20210510.0-35-g2ac6b7688 (automated)
Diffstat (limited to 'pkg/buffer/safemem.go')
-rw-r--r--pkg/buffer/safemem.go133
1 files changed, 0 insertions, 133 deletions
diff --git a/pkg/buffer/safemem.go b/pkg/buffer/safemem.go
deleted file mode 100644
index 8b42575b4..000000000
--- a/pkg/buffer/safemem.go
+++ /dev/null
@@ -1,133 +0,0 @@
-// Copyright 2020 The gVisor Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package buffer
-
-import (
- "gvisor.dev/gvisor/pkg/safemem"
-)
-
-// WriteBlock returns this buffer as a write Block.
-func (b *buffer) WriteBlock() safemem.Block {
- return safemem.BlockFromSafeSlice(b.WriteSlice())
-}
-
-// ReadBlock returns this buffer as a read Block.
-func (b *buffer) ReadBlock() safemem.Block {
- return safemem.BlockFromSafeSlice(b.ReadSlice())
-}
-
-// WriteFromSafememReader writes up to count bytes from r to v and advances the
-// write index by the number of bytes written. It calls r.ReadToBlocks() at
-// most once.
-func (v *View) WriteFromSafememReader(r safemem.Reader, count uint64) (uint64, error) {
- if count == 0 {
- return 0, nil
- }
-
- var (
- dst safemem.BlockSeq
- blocks []safemem.Block
- )
-
- // Need at least one buffer.
- firstBuf := v.data.Back()
- if firstBuf == nil {
- firstBuf = v.pool.get()
- v.data.PushBack(firstBuf)
- }
-
- // Does the last block have sufficient capacity alone?
- if l := uint64(firstBuf.WriteSize()); l >= count {
- dst = safemem.BlockSeqOf(firstBuf.WriteBlock().TakeFirst64(count))
- } else {
- // Append blocks until sufficient.
- count -= l
- blocks = append(blocks, firstBuf.WriteBlock())
- for count > 0 {
- emptyBuf := v.pool.get()
- v.data.PushBack(emptyBuf)
- block := emptyBuf.WriteBlock().TakeFirst64(count)
- count -= uint64(block.Len())
- blocks = append(blocks, block)
- }
- dst = safemem.BlockSeqFromSlice(blocks)
- }
-
- // Perform I/O.
- n, err := r.ReadToBlocks(dst)
- v.size += int64(n)
-
- // Update all indices.
- for left := n; left > 0; firstBuf = firstBuf.Next() {
- if l := firstBuf.WriteSize(); left >= uint64(l) {
- firstBuf.WriteMove(l) // Whole block.
- left -= uint64(l)
- } else {
- firstBuf.WriteMove(int(left)) // Partial block.
- left = 0
- }
- }
-
- return n, err
-}
-
-// WriteFromBlocks implements safemem.Writer.WriteFromBlocks. It advances the
-// write index by the number of bytes written.
-func (v *View) WriteFromBlocks(srcs safemem.BlockSeq) (uint64, error) {
- return v.WriteFromSafememReader(&safemem.BlockSeqReader{srcs}, srcs.NumBytes())
-}
-
-// ReadToSafememWriter reads up to count bytes from v to w. It does not advance
-// the read index. It calls w.WriteFromBlocks() at most once.
-func (v *View) ReadToSafememWriter(w safemem.Writer, count uint64) (uint64, error) {
- if count == 0 {
- return 0, nil
- }
-
- var (
- src safemem.BlockSeq
- blocks []safemem.Block
- )
-
- firstBuf := v.data.Front()
- if firstBuf == nil {
- return 0, nil // No EOF.
- }
-
- // Is all the data in a single block?
- if l := uint64(firstBuf.ReadSize()); l >= count {
- src = safemem.BlockSeqOf(firstBuf.ReadBlock().TakeFirst64(count))
- } else {
- // Build a list of all the buffers.
- count -= l
- blocks = append(blocks, firstBuf.ReadBlock())
- for buf := firstBuf.Next(); buf != nil && count > 0; buf = buf.Next() {
- block := buf.ReadBlock().TakeFirst64(count)
- count -= uint64(block.Len())
- blocks = append(blocks, block)
- }
- src = safemem.BlockSeqFromSlice(blocks)
- }
-
- // Perform I/O. As documented, we don't advance the read index.
- return w.WriteFromBlocks(src)
-}
-
-// ReadToBlocks implements safemem.Reader.ReadToBlocks. It does not advance the
-// read index by the number of bytes read, such that it's only safe to call if
-// the caller guarantees that ReadToBlocks will only be called once.
-func (v *View) ReadToBlocks(dsts safemem.BlockSeq) (uint64, error) {
- return v.ReadToSafememWriter(&safemem.BlockSeqWriter{dsts}, dsts.NumBytes())
-}